docs: def _load_stop_words(self, language=None):
          """Load stop words into __stop_words set.
  
          Stop words will be loaded according to the language code
          received during instantiation.
  
          Args:
              language: Language code.
  
          Returns:
              A boolean indicating whether a file was loaded.
          """
          self._logger.debug('Loading stop words')
  
          loaded = False
  
          if language:
              file_path = 'data/stop-' + language
              loaded = self._parse_stop_words_file(os.path.join(PATH, file_path))
          else:
              for file in os.listdir(os.path.join(PATH, 'data')):
                  loaded = self._parse_stop_words_file(os.path.join(PATH, 'data', file)) or loaded
  
          return loaded